/*
This file is part of the iText (R) project.
Copyright (c) 1998-2025 Apryse Group NV
Authors: Apryse Software.

This program is offered under a commercial and under the AGPL license.
For commercial licensing, contact us at https://itextpdf.com/sales.  For AGPL licensing, see below.

AGPL licensing:
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Affero General Public License for more details.

You should have received a copy of the GNU Affero General Public License
along with this program.  If not, see <https://www.gnu.org/licenses/>.
*/
using System.IO;
using iText.Kernel.Pdf.Filters;

namespace iText.Kernel.Pdf {
    /// <summary>Handles memory limits aware processing.</summary>
    /// <seealso cref="MemoryLimitsAwareHandler"/>
    public abstract class MemoryLimitsAwareFilter : IFilterHandler {
        /// <summary>
        /// Creates a
        /// <see cref="MemoryLimitsAwareOutputStream"/>
        /// which will be used for decompression of the passed pdf stream.
        /// </summary>
        /// <param name="streamDictionary">the pdf stream which is going to be decompressed.</param>
        /// <returns>
        /// the
        /// <see cref="System.IO.MemoryStream"/>
        /// which will be used for decompression of the passed pdf stream
        /// </returns>
        public virtual MemoryStream EnableMemoryLimitsAwareHandler(PdfDictionary streamDictionary) {
            MemoryLimitsAwareOutputStream outputStream = new MemoryLimitsAwareOutputStream();
            MemoryLimitsAwareHandler memoryLimitsAwareHandler = null;
            if (null != streamDictionary.GetIndirectReference()) {
                memoryLimitsAwareHandler = streamDictionary.GetIndirectReference().GetDocument().GetMemoryLimitsAwareHandler
                    ();
            }
            else {
                // We do not reuse some static instance because one can process pdfs in different threads.
                memoryLimitsAwareHandler = new MemoryLimitsAwareHandler();
            }
            if (null != memoryLimitsAwareHandler && memoryLimitsAwareHandler.considerCurrentPdfStream) {
                outputStream.SetMaxStreamSize(memoryLimitsAwareHandler.GetMaxSizeOfSingleDecompressedPdfStream());
            }
            return outputStream;
        }

        public abstract byte[] Decode(byte[] arg1, PdfName arg2, PdfObject arg3, PdfDictionary arg4);
    }
}
